Luis has biked his bike for a total of $16$ miles since he started biking daily. He has been biking $4$ miles each day. For how many days has Luis been biking?
Answer: The number of days that Luis has been biking is the total number of miles biked divided by the number of miles biked each day. $16\text{ miles} \div 4\text{ miles per day} = \text{number of days biking}$ $16\text{ miles} \div 4\text{ miles per day} = 4\text{ days}$